Valve cover and liner retainer for a fluid end of a pump

ABSTRACT

A valve cover assembly and a liner retainer assembly configured to retain a plug, a liner, and/or a liner seal within or against a module or retention body of a fluid end of a pump. The valve cover assembly and the liner retainer assembly include pistons coupled to a retaining flange or a threaded gland. A bias applied to the pistons biases the retaining flange and a threaded gland that is coupled to the retaining flange, or the piston alone, into engagement with the module or retention body to retain the plug, the liner, and/or the liner seal on the module.

BACKGROUND

Field of the Disclosure

Embodiments of the present disclosure generally relate to a fluid endmodule that integrates a valve cover and/or liner retention system.

Description of the Related Art

Multiplex reciprocating pumps are commonly used in the oil and gasindustry. The pumps are used to pump fluids at high pressure into one ormore wells comprising boreholes that are drilled into the ground.Multiplex pumps comprise a power end housing a crankshaft and acrosshead, and a fluid end having fluid bores in which individualplungers having intake and discharge valves reciprocate. Connecting rodsconnect the crosshead to the plungers to cause reciprocating motion ofthe plungers in the fluid bores to move fluid from a suction end to adischarge end of the fluid bores. The fluid end components (e.g. screwglands, covers, valves, pistons, liners, seals, etc.) have to bereplaced frequently because the fluids pumped through the fluid end areabrasive, corrosive, and/or are pumped at high pressures and flow rates,which cause wear on the fluid end components.

Removing one or more fluid end components, and installing replacementcomponents therein, can be difficult due to space limitations and customtools, which may be required for the installation/removal of components.Access to the fluid end may be limited by the presence of adjacent heavymachinery, including the power end of the pump, which limits the amountof working space available to access components needing to be replaced.Installing and removing a valve cover or a liner retainer of the fluidend, for example, requires using a long cheater bar, tommy bar, orC-spanner and a heavy hammer to provide sufficient torque to unbolt thevalve cover or liner retainer, and the limited clearance between thefluid end and adjacent equipment may make it impossible to insert a longbar in a location to access the components being replaced. Also,hammering the long cheater bar, tommy bar, or C-spanner by swinging theheavy hammer to unbolt the valve cover or the liner retainer of thefluid end, when combined with the limited amount of working space,increases safety hazard risks for the workers installing/removing thesecomponents.

Therefore, there is a continuous need for new and improved fluid enddesigns with components that are easy to install/remove and thatincrease worker safety.

SUMMARY OF THE DISCLOSURE

In one embodiment, an assembly comprises a body; a piston extending fromthe body; a biasing member biasing the piston into the body; and aretaining flange coupled to the piston, wherein the retaining flange isbiased toward the body by a bias applied to the piston by the biasingmember.

In one embodiment, a method of installing an assembly comprisespositioning a retaining flange relative to a body such that a pistonextending from the body extends into an opening of the retaining flange;supplying pressurized fluid into a chamber formed in the body to movethe piston against a bias applied on the piston by a biasing memberdisposed within the body; coupling a flange retaining nut to the pistonsuch that the flange retaining nut engages the retaining flange; andforcing the retaining flange toward the body by the force applied to thepiston by the biasing member.

In one embodiment, an assembly comprises a module; a threaded glandcoupled to the module; a piston at least partially disposed within thethreaded gland; and a biasing member disposed within the threaded glandand biasing the piston toward the module.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features can be understoodin detail, a more particular description of the embodiments, brieflysummarized above, may be had by reference to embodiments, some of whichare illustrated in the appended drawings. It is to be noted, however,that the appended drawings illustrate only typical embodiments and aretherefore not to be considered limiting of its scope, for theembodiments may admit to other equally effective embodiments.

FIG. 1 illustrates a first sectional view of a fluid end, according toone embodiment disclosed herein.

FIG. 2 illustrates a second sectional view of the fluid end, accordingto one embodiment disclosed herein.

FIG. 3 illustrates a third sectional view of the fluid end, according toone embodiment disclosed herein.

FIGS. 4A, 4B, and 4C illustrate enlarged sectional views of a valvecover, according to one embodiment disclosed herein.

FIGS. 5A, 5B, and 5C illustrate enlarged sectional views of a linerretainer, according to one embodiment disclosed herein.

FIG. 6 illustrates a first sectional view of another fluid end,according to one embodiment disclosed herein.

FIGS. 7A, 7B, and 7C illustrate enlarged sectional views of anothervalve cover, according to one embodiment disclosed herein.

FIGS. 8A, 8B, and 8C illustrate enlarged sectional views of anotherliner retainer, according to one embodiment disclosed herein.

DETAILED DESCRIPTION

FIG. 1 and FIG. 6 illustrate fluid ends 100, 200 of a multiplexreciprocating pump. Examples of a multiplex reciprocating pump that canbe used with the embodiments disclosed herein are described in U.S.Patent Application Publication No. 2013/0263932, filed on Mar. 15, 2013,the contents of which are herein incorporated by reference in itsentirety. Although the embodiments of the fluid ends 100, 200 aredescribed herein as a component of a multiplex reciprocating pump, theembodiments of the fluid ends 100, 200 can be used with other types ofequipment.

As illustrated in FIG. 1 and FIG. 2, the fluid end 100 includes a module10 (e.g., a unitary metallic body) having an intermediate flow bore 11in fluid communication with a discharge flow bore 12 at one end thereofand a suction flow bore 13 at an opposite end thereof. The internalcomponents of the fluid end 100, including a reciprocating plunger topump fluid into the suction flow bore 13 and a valve to control fluidflow into the discharge flow bore 12, have not been illustrated forclarity of the description of the fluid end 100. The fluid end 100includes a valve cover assembly 110 on one side 10 a thereof, and aliner retainer assembly 120 at a second side 10 b thereof. The valvecover assembly 110 and the liner retainer assembly 120 are located atopposite ends of the flow bores 11, 12, 13.

The valve cover assembly 110 includes a retaining flange 15 that isattached to one side 10 a of the module 10 by one or more flangeretaining nuts 16. The retaining flange 15 includes a threaded bore intowhich a threaded gland 18 is threaded to retain a plug 17 within themodule 10. The threaded gland 18 can be un-threaded from the retainingflange 15 to remove the plug 17 and provide access to the componentswithin the module 10 without having to remove the retaining flange 15.The retaining flange 15, the threaded gland 18, and the plug 17 areconfigured to contain pressurized fluid flowing through the flow bores11, 12, 13 within the body 10 during operation of the fluid end 100.

The liner retainer assembly 120 includes a retaining flange 22 that isattached to the second side 10 b of the module 10 by one or more flangeretaining nuts 23. The retaining flange 22 includes a threaded borewithin which a threaded gland 21 is received to retain a liner 20against a liner seal 24 that is held within the module 10. The threadedgland 21 includes internal threads that are threaded into engagementwith external threads formed on the outer surface from the liner 20. Theretaining flange 22, the threaded gland 21, the liner 20, and the linerseal 24 are configured to contain pressurized fluid flowing through theflow bores 11, 12, 13 within the body 10 during operation of the fluidend 100.

As illustrated in FIG. 3, the valve cover assembly 110 further includesone or more pistons 14 that are at least partially disposed within bores10 c extending inwardly of the module 10. The pistons 14 are biasedinwardly of the module 10 by one or more biasing members 19, such assprings, which at a first end thereof bear against a circumferentialflange portion 26 extending around the pistons 14. The biasing members19 and the pistons 14 are retained within the bores 10 c of the module10 by one or more piston retaining nuts 25 that are coupled to themodule 10, and against which a second end of the biasing members 19bear.

The piston retaining nuts 25 are threaded into threaded counterboresextending into the one side 10 a of the module 10 to contain the biasingmembers 19 and the pistons 14 within the module 10. One or more sealscan be disposed between the pistons 14 and the piston retaining nuts 25,as well as between the flange portions 26 of the pistons 14 and themodule 10, to form a seal between adjacent surfaces. Pressurized fluidcan be supplied into chambers 28, which are formed within the module 10below the pistons 14, via one or more fluid paths 27 disposed throughthe module 10 to cause the pistons 14 to move against the force of thebiasing members 19, as further described below with respect to FIGS.4A-4C.

The pistons 14, in combination with the flange retaining nuts 16, areconfigured to bias the retaining flange 15 against the one side 10 a ofthe module 10. The pistons 14 extend through the biasing members 19 andthe piston retaining nuts 25, and into corresponding openings formed inthe retaining flange 15 for connection therein to the flange retainingnuts 16. The flange retaining nuts 16 include an inner threaded bore 16a which is threaded into engagement with the threaded upper ends 14 a ofthe pistons 14 until a shoulder of the flange retaining nuts 16 contactsthe upper surface of the retaining flange 15. To secure the retainingflange 15 to one side 10 a of the module 10, the biasing members 14apply a force onto the flange portion 26 of the pistons 14 to bias thepistons 14 inwardly of the bores 10 c, which biases the flange retainingnuts 16 and the retaining flange 15 over which they are positionedagainst the one side 10 a of the module 10, thereby biasing the threadedgland 18 against the plug 17. Thus, the valve cover assembly 110provides a force on the plug 17 to effectively seal and containpressurized fluid within the module 10 during operation of the fluid end100.

As further illustrated in FIG. 3, the liner retainer assembly 110likewise includes one or more pistons 29 that are at least partiallydisposed within bores 10 d extending inwardly of the module 10 at thesecond side 10 b. The pistons 29 are biased inwardly of the module 10 byone or more biasing members 30, such as springs, which contact a flangeportion 31 of the pistons 29. The biasing members 30 and the pistons 29are retained within the bores 10 d of the module 10 by one or morepiston retaining nuts 35 that are coupled to the module 10, and againstwhich a second end of the biasing members 30 bear.

The piston retaining nuts 35 are threaded into threaded counterbores ofthe module 10 to contain the biasing members 30 and the pistons 29within the module 10. One or more seals can be disposed between thepistons 29 and the piston retaining nuts 35, as well as between theflange portions 31 of the pistons 29 and the module 10, to form a sealbetween adjacent surfaces. Pressurized fluid can be supplied intochambers 33, which are formed within the module 10 below the pistons 29,via one or more fluid paths 32 disposed through the module 10 to movethe pistons 29 against the force of the biasing members 30, as furtherdescribed below with respect to FIGS. 5A-5C.

The pistons 29 extend through the biasing members 30 and the pistonretaining nuts 35, and into corresponding openings formed in theretaining flange 22 for connection to the flange retaining nuts 23. Theflange retaining nuts 23 are threaded into engagement with the upperends of the pistons 29 until a shoulder of the flange retaining nuts 23contacts the upper surface of the retaining flange 22. In this manner,the biasing members 30 apply a bias against the flange portion 31 of thepistons 29, which pulls the flange retaining nuts 23 and the retainingflange 22 toward the module 10, thereby forcing the threaded gland 21and the liner 20 against the liner seal 24. The liner retainer assembly110 provides a force on the liner seal 24 to effectively seal andcontain pressurized fluid within the module 10 during operation of thefluid end 100.

FIG. 4A, FIG. 4B, and FIG. 4C illustrate sectional views of the valvecover assembly 110 during installation, according to one embodiment.Referring to FIG. 4A, after the plug 17 is installed in the module 10(as shown in FIG. 2), the retaining flange 15 is positioned on themodule 10 such that the pistons 14 extend through the correspondingopenings formed in the retaining flange 15. The threaded gland 18 can bethreaded into the retaining flange 15 and onto the plug 17 (as shown inFIG. 2).

Referring to FIG. 4B, pressurized fluid (identified by reference arrow“F”) is supplied into the chambers 28 via the fluid paths 27. Thepressurized fluid forces the pistons 14 to extend further outwardly fromthe module 10 against the force of the biasing members 19 and therebycompress the biasing members 19. The pressurized fluid is supplied at apressure sufficient to generate a force on the flange portion 26 of thepistons 14 that compresses the biasing members 19 between the flangeportion 26 and the piston retaining nuts 25. While the chambers 28 arepressurized and the pistons 14 are compressing the biasing members 19,the flange retaining nuts 16 can be threaded onto the upper ends of thepistons 14 until the shoulder of the flange retaining nuts 16 contactsthe upper surface of the retaining flange 15.

Referring to FIG. 4C, after the flange retaining nuts 16 are coupled tothe pistons 14, the pressurized fluid is vented from the chambers 28and/or the pressure within the chambers 28 is reduced such that thebiasing members 19 create a force on the pistons 14 that forces thepistons 14 to pull the retaining flange 15 and the threaded gland 18against the plug 17 to seal off the flow bores 11, 12, 13 of the module10. In this manner, the plug 17 is held within the module 10 by theforce produced by the biasing members 19 acting on the pistons 14.

To remove the retaining flange 15, the installation process describedwith respect to FIGS. 4A-4C can be repeated in reverse order.Pressurized fluid may be supplied into the chambers 28 to force thepistons 14 to compress the biasing members 19 and at least partiallyextend the flange retaining nuts 16 away from the retaining flange 15 tounscrew the flange retaining nuts 16 from the pistons 14. Thepressurized fluid can be released from the chambers 29 beforeunthreading the threaded gland 18 from the retaining flange 15.Alternatively, the threaded gland 21 can be unscrewed while supplyingpressurized fluid into the chambers 28. By extending the flangeretaining nuts 16 away from the module 10, the frictional sticking forcebetween the underside of the flange retaining nuts 16 and the retainingflange 15 is reduced or eliminated, enabling the removal of the flangeretaining nuts 16 and the retaining flange 15 without the high torquerequired in the prior art.

FIG. 5A, FIG. 5B, and FIG. 5C illustrate sectional views of the linerretainer assembly 120 during installation, according to one embodiment.Referring to FIG. 5A, after the liner seal 24 and the liner 20 areinstalled in the module 10 (as shown in FIG. 2), the retaining flange 22is positioned on the module 10 such that the pistons 29 extend throughthe corresponding openings formed in the retaining flange 22. Thethreaded gland 21 can be threaded into the retaining flange 22 and ontoa shoulder of the liner 20.

Referring to FIG. 5B, a pressurized fluid (identified by reference arrow“F”) is supplied into the chambers 33 via the fluid paths 32. Thepressurized fluid forces the pistons 29 to extend further outwardly fromthe module 10 against the force of the biasing members 30. Thepressurized fluid is supplied at a pressure sufficient to generate aforce on the flange portion 31 of the pistons 29 that compresses thebiasing members 30 between the flange portion 31 and the pistonretaining nuts 35. While the chambers 33 are pressurized and the pistons29 are compressing the biasing members 30, the flange retaining nuts 23are threaded onto the upper ends of the pistons 19 until the shoulder ofthe flange retaining nuts 23 contacts the upper surface of the retainingflange 22.

Referring to FIG. 5C, after the flange retaining nuts 23 are coupled tothe pistons 29, the pressurized fluid can be released from the chambers33 and/or the pressure within the chambers 33 can be reduced such thatthe biasing members 30 create a force on the pistons 29 that biases thepistons 29 inwardly of the module 10 to bias the retaining flange 22 andthe threaded gland 21 against the liner 20 and the liner seal 24 to sealoff the flow bores 11, 12, 13 of the module 10. In this manner, theliner seal 24 is held within the module 10 by the force produced by thebiasing members 30 acting on the pistons 29.

To remove the retaining flange 22, the installation process describedwith respect to FIGS. 5A-5C can be repeated in reverse order.Pressurized fluid may be supplied into the chambers 33 to force thepistons 29 to compress the biasing members 19 and at least partiallyextend the flange retaining nuts 23 away from the retaining flange 22 tounscrew the flange retaining nuts 23 from the pistons 29. Thepressurized fluid can be released from the chambers 33 beforeunthreading the threaded gland 21 from the retaining flange 22.Alternatively, the threaded gland 21 can be unscrewed while supplyingpressurized fluid into the chambers 33. As with the retaining flange 15,the retaining flange 22 is thus removed with lower unthreading torque onthe flange retaining nuts 23.

FIG. 6 illustrates a sectional view of a fluid end 200. The fluid end200 has many similar elements as the fluid end 100 and a fulldescription of all the elements will not be repeated for brevity. Someelements of the fluid end 200 that are similar to the elements of thefluid end 100 are identified with the same reference number but having a200 series designation. The embodiments of the fluid end 200 can be usedwith the embodiments of the fluid end 100 and vice versa.

The fluid end 200 includes a module 210 (e.g., a unitary metallic body)having a valve cover assembly 201 coupled to one side, and a linerretainer assembly 202 coupled to another side. The valve cover assembly201 and the liner retainer assembly 202 are located at opposite ends ofone or more flow bores formed through the module 210. The valve coverassembly 201 and the liner retainer assembly 201 are configured toeffectively seal and contain pressurized fluid within the module 210during operation of the fluid end 200.

The valve cover assembly 201 includes a retaining flange 215 that isattached to the module 210 by one or more flange retaining nuts/bolts216. The retaining flange 215 includes a threaded bore into which athreaded gland 218 is threaded to retain a plug 217 within the module210. The threaded gland 218 can be un-threaded from the retaining flange215 to remove the plug 217 and provide access to the components withinthe module 210 without having to remove the retaining flange 215. Theretaining flange 215, the threaded gland 218, and the plug 217 areconfigured to contain pressurized fluid flowing through the flow boreswithin the module 210 during operation of the fluid end 200.

The valve cover assembly 201 further includes a piston 214 that is atleast partially disposed within a bore of the threaded gland 218. Thepiston 214 is biased toward the module 210 by one or more biasingmembers 219, such as springs, which at a first end thereof bear againsta flange portion 226 extending around the piston 214. The biasingmembers 219 and the piston 214 are retained within the bore of thethreaded gland 218 by a piston retaining nut 225 that is coupled to thethreaded gland 218, and against which a second end of the biasingmembers 219 contact. An upper portion of the piston 214 extends througha bore of the piston retaining nut 225.

The piston retaining nut 225 is threaded into engagement with internalthreads formed in the bore of the threaded gland 218 to contain thebiasing members 219 and the piston 214. One or more seals can bedisposed between the piston 214 and the piston retaining nut 225, aswell as between the piston 214 and the threaded gland 218, to form aseal between adjacent surfaces. Pressurized fluid can be supplied into achamber 228, which is formed within the threaded gland 218 below theflange portion 226 of the piston 214, via one or more fluid paths 227that are disposed through the piston 214. The pressurized fluid suppliedinto the chamber 228 causes the piston 214 to move against the force ofthe biasing members 219, as further described below with respect toFIGS. 7A-7C.

The liner retainer assembly 202 is coupled to another side of the module210. The liner retainer assembly 202 includes a retaining flange 222that is attached to a retention body 240 by one or more pistons 229 andone or more flange retaining nuts 223. The retaining flange 222 has oneor more handles 243 for ease of handling during installation andremoval. A spacer 241 is positioned between the retention body 240 andthe module 210. One or more nuts 245 and bolts 244 are used to couplethe retention body 240 and the spacer 241 to the module 210.

The retaining flange 222, the retention body 240, and the spacer 241include a bore through which a liner 220 is positioned to secure a linerseal 224 within the module 210. The liner 220 includes an outer shoulder221 that is disposed between one end of the retaining flange 222 and aninner shoulder of the retention body 240. The retaining flange 222, theretention body 240, the spacer 241, the liner 220, and the liner seal224 are configured to contain pressurized fluid flowing through the flowbores within the module 210 during operation of the fluid end 200.

The pistons 229 are biased toward the module 210 (and inwardly relativeto the retention body 240) by one or more biasing members 230, such assprings, which contact a flange portion 231 of the pistons 229 at afirst end. The biasing members 230 and the pistons 229 are retainedwithin the retention body 240 by one or more piston retaining nuts 235that are coupled to the retention body 240, and against which a secondend of the biasing members 230 contact. The piston retaining nuts 235are threaded into threaded counterbores of the retention body 240 tocontain the biasing members 230 and the pistons 229. One or more sealscan be disposed between the pistons 229 and the piston retaining nuts235, as well as between the flange portions 231 of the pistons 229 andthe retention body 240, to form a seal between adjacent surfaces.

An upper portion of the pistons 229 extends through the biasing members230 and the piston retaining nuts 235, and into corresponding openingsformed in the retaining flange 222 for connection to the flangeretaining nuts 223. The flange retaining nuts 223 are threaded intoengagement with the upper ends of the pistons 229 until the flangeretaining nuts 223 contact the upper surface of the retaining flange222. The biasing members 230 apply a bias against the flange portion 231of the pistons 229, which pulls the flange retaining nuts 223 and theretaining flange 222 against the outer shoulder 221 of the liner 220,thereby forcing or retaining the liner 220 against the liner seal 224,as further described below with respect to FIGS. 8A-8C.

FIG. 7A, FIG. 7B, and FIG. 7C illustrate sectional views of the valvecover assembly 201 during installation, according to one embodiment.Referring to FIG. 7A, the retaining flange 215 is bolted to the module210 using the flange retaining nuts/bolts 216. The plug 217 is installedin the module 210 before or after the retaining flange 215 is attachedto the module 210. The threaded gland 218 is threaded into the retainingflange 215 until a lower portion 250 of the piston 214 engages a topsurface of the plug 217. The lower portion of 250 of the piston 214 isdisposed through a bore formed in the bottom end of the threaded gland218.

Referring to FIG. 7B, pressurized fluid (identified by reference arrow“F”) is supplied into the chamber 228 via the fluid paths 227. Thepressurized fluid forces the piston 214 to move away from the plug 217and against the force of the biasing members 219, thereby compressingthe biasing members 219. The pressurized fluid is supplied at a pressuresufficient to generate a force on the flange portion 226 of the piston214 that compresses the biasing members 219 between the flange portion226 and the piston retaining nut 225.

Referring to FIG. 7C, while the chamber 228 is pressurized and thepiston 214 is compressing the biasing members 219, the threaded gland218 can be threaded further into the retaining flange 215 until thelower portion 250 of the piston 214 engages the top surface of the plug217. The pressurized fluid is then vented from the chamber 228 and/orthe pressure within the chamber 228 is reduced such that the biasingmembers 219 create a force on the piston 214 that forces the piston 214against the plug 217. In this manner, the plug 217 is held within themodule 210 by the force produced by the biasing members 219 acting onthe pistons 214. To remove the retaining flange 215, the installationprocess described with respect to FIGS. 7A-7C can be repeated in reverseorder.

FIG. 8A, FIG. 8B, and FIG. 8C illustrate sectional views of the linerretainer assembly 202 as shown in FIG. 6 during installation, accordingto one embodiment. Referring to FIG. 8A, the spacer 241 and theretention body 240 are coupled to the module 210 via the nuts 245 andbolts 244. The liner 220 is inserted into the bores of the retentionbody 240 and the spacer 241 and against the liner seal 224 disposedwithin the module 210 (as shown in FIG. 6). The retaining flange 222 isinserted into the bore of the retention body 240 such that the outershoulder 221 of the liner 220 is disposed between the inner shoulder ofthe retention body 240 and the bottom end of the retaining flange 222.The pistons 229 extend through corresponding openings formed in theretaining flange 222, and the flange retaining nuts 223 are threadedonto the pistons 229 to couple the retaining flange 222 to the retentionbody 240.

Referring to FIG. 8B, a pressurized fluid is supplied into chambers 233formed within the retention body 240 below the flange portion 231 of thepistons 229. The pressurized fluid forces the pistons 229 to extendoutwardly from the retention body 240 against the force of the biasingmembers 230. The pressurized fluid is supplied at a pressure sufficientto generate a force on the flange portion 231 of the pistons 229 thatcompresses the biasing members 230 between the flange portion 231 andthe piston retaining nuts 235. While the chambers 233 are pressurizedand the pistons 229 are compressing the biasing members 230, the flangeretaining nuts 223 are threaded further onto the upper ends of thepistons 229 and into contact with the upper surface of the retainingflange 222.

Referring to FIG. 8C, after the flange retaining nuts 223 are threadedfurther onto the pistons 229, the pressurized fluid can be released fromthe chambers 233 and/or the pressure within the chambers 233 can bereduced such that the biasing members 230 create a force on the pistons229 that biases the retaining flange 222 against the outer shoulder 221of the liner 220. In this manner, the liner seal 224 is held within themodule 210 by the force produced by the biasing members 230 acting onthe pistons 229 to force the retaining flange 222 against the liner 220.To remove the retaining flange 222, the installation process describedwith respect to FIGS. 8A-8C can be repeated in reverse order.

One advantage of the valve cover assembly 110, 201 and the linerretainer assembly 120, 202 is an increase in worker safety byeliminating the need for using heavy (sledge) hammers duringinstallation and removal. Another advantage is a reduction of theinstallation and removal time by utilizing a bias member force ratherthan force supplied by threading a fastener into a retaining flange toseal around the openings in the sides of the modules 10, 210 of thefluid ends 100, 200. Another advantage is that existing fluid endmodules can be modified for use with the valve cover assembly 110, 201and the liner retainer assembly 120, 201 as described herein.

While the foregoing is directed to certain embodiments, other andfurther embodiments may be devised without departing from the basicscope thereof, and the scope thereof is determined by the claims thatfollow.

1. An assembly, comprising: a body; a piston extending from the body; abiasing member biasing the piston into the body; and a retaining flangecoupled to the piston, wherein the retaining flange is biased toward thebody by a bias applied to the piston by the biasing member.
 2. Theassembly of claim 1, wherein the body comprises a module of a fluid endor a separate retention body coupled to the module of the fluid end. 3.The assembly of claim 1, wherein the piston includes a flange portiondisposed within the body, and wherein the bias of the biasing member isapplied to the flange portion.
 4. The assembly of claim 1, wherein theretaining flange is coupled to the piston by a flange retaining nutwhich engages the retaining flange.
 5. The assembly of claim 1, whereinthe biasing member is retained within the body by a piston retaining nutthat is coupled to the body.
 6. The assembly of claim 1, wherein achamber is formed within the body at a position below the piston suchthat application of pressurized fluid into the chamber moves the pistonagainst the bias of the biasing member.
 7. The assembly of claim 1,further comprising a threaded gland coupled to the retaining flange andconfigured to retain at least one of a plug, a liner, and a liner sealwithin or against the module.
 8. The assembly of claim 1, wherein thebody comprises a separate retention body coupled to a module of a fluidend, and wherein the retaining flange is biased toward the retentionbody to retain a liner against the module.
 9. A method of installing anassembly, comprising: positioning a retaining flange relative to a bodysuch that a piston extending from the body extends into an opening ofthe retaining flange; supplying pressurized fluid into a chamber formedin the body to move the piston against a bias applied on the piston by abiasing member disposed within the body; coupling a flange retaining nutto the piston such that the flange retaining nut engages the retainingflange; and forcing the retaining flange toward the body by the forceapplied to the piston by the biasing member.
 10. The method of claim 9,wherein the body comprises a module of a fluid end or a separateretention body coupled to the module of the fluid end.
 11. The method ofclaim 9, further comprising reducing pressure within the chamber suchthat the force applied to the piston by the biasing member forces thepiston into the body.
 12. The method of claim 9, wherein the pistonincludes a flange portion disposed within the body, and wherein theforce of the biasing member is applied to the flange portion.
 13. Themethod of claim 9, further comprising threading a threaded gland intothe retaining flange to retain at least one of a plug, a liner, and aliner seal within or against the module.
 14. The method of claim 9,wherein the body comprises a separate retention body coupled to a moduleof a fluid end, and wherein the retaining flange is biased toward theretention body to retain a liner against the module.
 15. An assembly,comprising: a module; a threaded gland coupled to the module; a pistonat least partially disposed within the threaded gland; and a biasingmember disposed within the threaded gland and biasing the piston towardthe module.
 16. The assembly of claim 15, wherein the biasing member isretained within the threaded gland by a piston retaining nut that iscoupled to the threaded gland.
 17. The assembly of claim 15, wherein thepiston includes a flange portion disposed within the threaded gland, andwherein the bias of the biasing member is applied to the flange portion.18. The assembly of claim 17, wherein a chamber is formed within thethreaded gland at a position below the flange portion such thatapplication of pressurized fluid into the chamber moves the pistonagainst the bias of the biasing member.
 19. The assembly of claim 18,wherein a fluid path is formed through the piston to supply pressurizedfluid to the chamber.
 20. The assembly of claim 19, wherein a lowerportion of the piston extends through a bore formed in a bottom end ofthe threaded gland.